INTRODUCTORY NOTE. 



The surprising wealth of plumularian life in American waters was unknown to tbe earlier 

 investigators of the marine fauna of the New World, a fact due to the lack of exploration in the 

 West Indian region, which has since yielded an unprecedented harvest, the result of the scientific 

 work of those in charge of the vessels of the U. S. Coast and Geodetic Survey and the T. S. Fish 

 Commission. 



When, in 18CU, the elder Agassiz wrote the fourth volume of his Contributions to the Natural 

 History of the United States, only three species of Plumularida 1 were included. Three years later 

 his son, Alexander Agassiz, recognized six species in the second number of the Illustrated Cata- 

 logue of the Museum of Comparative Zoology. Two of these species, however, Aglaophenia 

 francisrana and Plumttlarin arborea, probably belong to the genus Hyd rail mania, and would there- 

 fore not be included in the Pluinularida-. 



A very important contribution to our knowledge of this group was made by Professor Allman 

 in 1877, when he published the results of his investigation of the material secured by Count 

 Pourtales in the Gulf Stream. 1 In that beautifully illustrated work no less than twenty-six 

 species of plumnlariaus are mentioned, twenty-four being new to science and hence carefully 

 described and figured. 



In 1879 Prof. A. E. Yerrill published his Preliminary Check-List of the Marine luvertebrata 

 of the Atlantic Coast from Cape Cod to the Gulf of St. Lawrence, in which seven species of 

 Pluniularid;e are noted. The material secured by the U. S. Coast and Geodetic Survey steamer 

 Hltrite in 1877-78 was reported on by Dr. S. F. Clark, 2 who found three new species. The same 

 vessel continued the work of dredging in the Southern waters during the remainder of 1878, 1879, 

 and the summer of 18SO, with the result that Dr. J. Walter Fewkes described twelve new species 

 of Plumularidie from the material secured. 3 



From 1871 to the present time an enormous amount of dredging has been done by the various 

 vessels employed in the work of the U. S. Fish Commission and U. S. Coast and Geodetic Survey. 

 As a result an unprecedented quantity of inaterial has accumulated in the U. S. National Museum 

 ami the museum of Yale University, which has been a sort of repository for the U. S. Fish Com- 

 mission collections, under charge of Prof. A. E. Verrill, who has done an almost incredible amount 

 of labor in working up various groups. He has only incidentally given attention to the hydroids, 

 however, and has described but few new species of Plumularida'. 



At the time of the inception of the present work it is doubtful if more than fifty species of 

 Plumularidie were known to occur in American waters. An examination of the wealth of material 

 above referred to resulted in the discovery of the numerous new species described in the following 

 pages. A careful scrutiny of the literature of the Hydroida also revealed a considerable number 

 of species that should be added to our fauna. 



It is now evident that the West Indian region is the richest in plumulariau life of any area, of 

 equal size in the world. Not even the Australian region, hitherto regarded as by far the most 

 prolific in these exceedingly graceful organisms, can equal our own Southern waters in profusion 

 of genera and species. 



1 Memoirs of the Museum of Comparative Zoology, V, No. 2, 1877. 



2 Report on the Hydroida collected during tbe exploration of the Gulf Stream and Gulf of Mexico by Alexander 

 Agassiz, 1877-78. Bulletin, Museum of Comparative Zoology, V, No. 10, 1879. 



: ' Report on the results of dredging, under the supervision of Alexander Agassi/., in the Caribbean Sea, in 

 1878-79, anil along the Atlantic coast of the United States, during the summer of 1880, by the U. S. Coast Survey 

 steamer Blakf, Commander J. R. Bartlett, U. S. N., commanding. Bulletin, Museum Comparative Zoology, VIII, 

 No. 7, 1881. 



1 



